Update 9.1 failed again and again on mini

I am typing message on iPad 2 to explain about 9.1 update problem cuz I cannot type anything on iPad mini. The message in discussion group won't respond to keyboard at all.

It began when I tried to update iOS to 9.1 on mini a week ago..but it failed again and again..it displayed downloading but hung there with hourglass running.. emails still work on mini. can type email messages.

But the 9.1 update was successful on iPad 2.